Marble and Stone Installation, New Britain & Across Connecticut

Two numbers. ANSI A108.02 tightens the flatness tolerance for natural stone, and for tile with an edge of 15 inches or more, to an eighth of an inch in 10 feet with no more than a sixteenth of an inch in 2 feet. Over wood framing, stone is held to L/720, the figure the Tile Council of North America and the Marble Institute of America both call for. We measure with a straight edge.

Real marble is porous, so it takes on water, it takes a sealer, and in a wet room it has to be sealed and resealed on a schedule. Marble-look porcelain is a different product: porcelain is fired vitrified and absorbs 0.5 percent or less under the ISO 13006 groups, so it never needs sealing for water resistance. Ask which one you are buying, then plan the sealing around it.

When it is wet, it can be, and no floor tile is slip proof. The number that matters is the wet DCOF, measured under ANSI A326.3, where 0.42 is the threshold for a level interior floor that gets walked on wet. A polished or honed stone floor often tests below that, and a shower floor is not a flat floor, it slopes to the drain. Ask for the wet number on the exact finish.

Each surface asks for something different. A wet room wants a slope to the drain, a bonded waterproofing system under the pan, and a flood test before any tile goes down. A floor wants a substrate that carries the weight and stays flat. A countertop wants a flat, square, waterproof base and a full bed of thinset. A wall wants taped and sealed backer board, and more care on a house that settles.

Most stone failures are substrate failures. A floor that moves cracks stone, a surface out of plane gives you lippage, and a wet room without a membrane behind it lets water into the wall. We check those first and tell you what we find before setting. The installation carries a 1-year written workmanship warranty, and it covers our work, not the stone, and not the resealing it needs over the years.